Abstract

Objectives Dementia with Lewy bodies (DLB) accounts for 10%–15% of dementia cases at autopsy and has distinct clinical features associated
with earlier institutionalisation and a higher level of carer distress than are seen in Alzheimer's disease (AD). At present,
there is on-going debate as to whether DLB is associated with a more rapid cognitive decline than AD. An understanding of
the rate of decline of cognitive and non-cognitive symptoms in DLB may help patients and carers to plan for the future.

Design In this cohort study, the authors compared 100 AD and 58 DLB subjects at baseline and at 12-month follow-up on cognitive
and neuropsychiatric measures.

Results The AD and DLB groups did not differ at baseline in terms of age, gender, Clinical Dementia Rating score and use of cholinesterase
inhibitors or memantine. NPI and NPI carer distress scores were statistically significantly higher for DLB subjects at baseline
and at follow-up, and there were no differences between AD and DLB in cognitive scores at baseline or at follow-up. There
was no significant difference in rate of progression of any of the variables analysed.

Conclusions DLB subjects had more neuropsychiatric features at baseline and at follow-up than AD, but the authors did not find any statistically
significant difference in rate of progression between the mild–moderate AD and DLB groups on cognitive or neuropsychiatric
measures over a 12-month follow-up period.

Footnotes

Author disclosure statements At the time of the study, ZW, JOB, IM, KT, JB and JD have received consultancy payments from
GE Healthcare. JR has received funding for neuroimaging research from GE Healthcare. TQ has no disclosures.

Contributors ZW: involved in conception and design of the study as well as being a member of the consensus panel, contributed to statistical
analysis and interpretation, co-wrote initial draft of the manuscript and prepared the final version of the manuscript; IM:
involved in conception and design of the study as well as being a member of the consensus panel, contributed to and approved
the final version of the manuscript; JR: involved in conception and design of the study, contributed to data analysis and
interpretation, co-wrote initial and subsequent drafts of the manuscript, contributed to and approved the final version of
the manuscript; TQ: involved in conception and design of the study, data processing, analysis and interpretation, contributed
to and approved the final version of the manuscript; KT: involved in conception and design of the study, performed the visual
analysis of the SPECT data, contributed to and approved the final version of the manuscript; JB: involved in conception and
design of the study, performed the visual analysis of the SPECT data, contributed to and approved the final version of the
manuscript; JD: involved in conception and design of the study, performed the visual analysis of the SPECT data, contributed
to and approved the final version of the manuscript; JOB: involved in conception and design of the study as well as being
a member of the consensus panel, contributed to and approved the final version of the manuscript.

Funding The data collection was sponsored by GE Healthcare who made data available for further analysis for the present study.